As far as I know, Guangzhou doesn't explicitly stipulate that restaurants can't use 5 kg gas cylinders to make hot pot. However, according to the "Guangzhou Catering Service Management Measures", when restaurants use gas or liquefied petroleum gas for cooking, they must abide by a series of safety regulations to ensure food safety and personnel safety. These provisions include but are not limited to:

1. The canteen must use special gas equipment to ensure safety and reliability;

2 gas equipment must be regularly overhauled and maintained, and passed the safety inspection;

3. Gas equipment must meet the relevant national standards and be equipped with automatic anti-overflow devices;

4. The gas equipment must be sealed to avoid gas leakage.

Restaurants using gas cylinders to make chafing dishes should abide by the above regulations, and ensure that the operators have relevant gas safety training and operation certificates. In addition, according to "Guangzhou Fire Protection Regulations", catering units should formulate a fire safety management system when using gas or liquefied petroleum gas equipment, and conduct regular inspections and training.

In a word, Guangzhou does not specifically require restaurants to use gas bottles to make hot pot, but restaurants need to comply with relevant gas use and fire safety regulations to ensure food safety and personnel safety. If there are specific needs, it is recommended to consult the relevant departments of the local government to obtain the latest policies and regulations.